Harvest Bosses not Phase Shifting in T16.5/T17 maps

I've done a few of these, but every time I did one at T17 the harvest bosses won't phase shift to the add phase and just keep spamming their high-damage moves. I don't have any issues in T16 maps, only T17s and Strand maps.

I've encountered the issue with Sentinels that affect unique enemies, Strand abilities that buff unique monsters in strand maps, Delirium, and Wildwood wisps. Pretty much if it affects a Harvest boss in T17s it bricks the harvest.